The present invention relates to a conveying boom system. In particular, the present invention relates to a system for supporting a conveying pipe system on the interior of a boom section.
Boom systems offer a safe, cost effective and efficient method of lifting a load and placing it in a distanced elevated position. Boom systems can be mounted on portable platforms such as trucks. Truck mounted boom systems are used as portable lifting and moving mechanisms, as well as to support piping for pumping liquids or semi-liquids. These boom systems typically have more than one boom section which makes up the overall boom system. Each boom section has a corresponding actuator assembly which moves the boom section (for example by articulating or telescoping the section).
Booms are commonly used in hazardous environments and must be articulated with precision to allow proper positioning of the boom. Boom systems known in prior art commonly support a conveying pipeline by attaching brackets to the exterior of the boom sections. The pipelines are used to direct liquids or semi-liquids, such as water or concrete. During positioning of the boom, inadvertent contact with external objects can occur. If contact occurs, it may result in undesirable damage to the boom and its exposed conveying pipeline. Using an externally mounted pipeline also causes clearance problems which occur when the boom is folded and deployed. The boom sections must be articulated in such a manner that the various sections of the pipeline do not contact each other (or the boom sections) during folding and deployment operation. Again, contact of the pipeline with the boom sections can result in damage to the externally attached pipeline.
While it is important to protect the conveying pipeline attached to the boom system, it is equally important that each boom section has as little weight as is reasonably possible. The weight of a boom at an outer section must be supported by the lower boom sections. Since each boom acts as a cantilever, the greater the weight of the boom and the load supported by the boom, the greater the moment generated by the boom with respect to the support system. If the boom is extended horizontally, the weight of the boom is moved farther away from the center of the gravity of the boom and support system, creating a large moment about the support system (i.e. the truck). The large moment causes an increased likelihood that the boom and support system may enter an unstable condition and tip over.
Mounting the pipeline externally along the boom sections introduces fatigue problems to the pipe support system. The eccentric loading of the boom sections can produce stresses at the connection point between the pipe supports and the pipeline. Additionally, when the liquid or semi-liquid is pumped through the pipeline, the pumping action can cause transverse and longitudinal forces to be imposed on the attached boom section. These forces are typically cyclical (particularly when a piston pump is being used as the pumping means) causing fatigue of the pipe supports due to the stresses induced by the eccentric loading. When piston type pumps are being used, a line shock occurs with each stroke of the piston. The force of the line shock causes the fluid to push longitudinally against the boom, thereby producing a force parallel but eccentric to the longitudinal axis of the boom. Again, this can fatigue the pipeline brackets, causing them to weaken and break so that the pipeline becomes unattached from the boom. To overcome problems with the strength of the support, the brackets necessarily must be larger, adding weight to the boom system and decreasing stability of the boom system at the boom support. Thus, there is a need in the art for a system for protecting conveying pipeline from damage caused by contact of a boom section with an external object and for mounting the pipeline along the axis of the boom sections, without significantly increasing the weight of the boom.
The invention is a placing boom comprising a plurality of boom sections connected together in an articulated arrangement. A pipeline is carried by the boom sections, wherein the pipeline is disposed inside at least one of the boom sections.